release: 0.122.0

[stainless-app]

Automated Release PR

0.122.0 (2026-08-13)

Full Changelog: v0.121.0...v0.122.0

Features

• api: add output_behavior to dream creation (create a new memory store or update the input store in place) (852c4bb)

Bug Fixes

• bedrock,aws: run SigV4 signing off the event loop in async clients (#334) (2bae6c8)
• bedrock: expose beta.messages.parse, stream and tool_runner (#366) (6eca7bb)
• client: add models (52e9d94)
• client: keep token exchange bound per client across copy() (#388) (c13e6e3)
• client: read PathLike contents passed inside a file tuple (070f953)
• client: treat empty ANTHROPIC_API_KEY / ANTHROPIC_AUTH_TOKEN as unset (#341) (76a2e68)
• streaming: add context to malformed tool input JSON errors in the non-beta accumulator (#339) (a343e17)
• streaming: apply all message_delta fields when accumulating streamed messages (#380) (fc1599b)
• streaming: emit input_json events for server tool use blocks (#336) (ccfc8e1)
• streaming: keep omitted content block fields unset in accumulated messages (#346) (cd40aab)
• streaming: run the request transform once in messages.stream() (#347) (81a92da)
• streaming: silence pydantic serializer warnings on message_stop events (#338) (41f9cdc)
• tools: reject symlink loops in tool paths and skip special skill-archive members (#322) (43e8669)
• vertex: expose beta.messages.parse and tool_runner (#367) (96723a0)

Chores

• ci: run breaking-change detection as a ci.yml job on every push (6dfd16e)
• examples: update messages_stream.py shebang from rye to uv (#1519) (7d72364)
• internal: codegen related update (21a0e3d)
• internal: drop remaining references to black (13df390)
• internal: remove misc things (d6ee99e)
• tests: use pytest monkeypatch and fakes instead of unittest.mock (55d246f)
• tests: use pytest monkeypatch instead of unittest.mock (e0c6488)

Documentation

• api: clarify that user profile name is optional for resold profiles (b8f9f61)
• fix fulfillment typos in session runner (#1795) (009b035)
• fix incorrect docstring in AsyncAnthropicFoundry.models (#1592) (f1f5e9b)

Refactors

• use the not_given singleton instead of the legacy NOT_GIVEN alias (eeb4d74)

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📚 Read the docs
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[stainless-app]

🧪 Testing

To try out this version of the SDK:

pip install 'https://pkg.stainless.com/s/anthropic-python/e0c64881c24291b77e2b0653994ac9e3c696ab00/anthropic-0.121.0-py3-none-any.whl'

Expires at: Sat, 12 Sep 2026 18:20:13 GMT
Updated at: Thu, 13 Aug 2026 18:20:13 GMT

[stainless-app]

🤖 Release is at https://github.com/anthropics/anthropic-sdk-python/releases/tag/v0.122.0 🌻